mistress. >> we have learned the pentagon is investigating another military official in the case. >> and a new twist, the pentagon now says that the top american commander in afghanistan donald john allen is under investigation for sending allegedly improper e-mails. kelly the florida woman that triggered the investigation that forced him to resign. they are reviewing between 20,000 and 30,000 documents involved. john allen denies any wrongdoing. agents by nearly five hours at the home of impala broadwell this after the fbi told abc news they discovered thousands of e- mails between her and him detailing the affair. >> and his universe this moral failing is unacceptable and renders them on worthy of continuing this position. >> you can do it for the summer. part of an fbi investigation that began after joe kelly received threatening e-mails she believed or from -- >> this caused them to take all the way through to see what they had a. >> basis yet classified material on your computer which is illegal. the fbi does not believe any of it came from him. no charges have been filed.